package com.wct.demo.gui;

import javax.swing.*;
import java.awt.*;

/**
 * @author WEI (Email:changtan20000@163.com)
 * @description
 * @date: 2019/12/22 13:46
 */
public class GridLayoutDemo extends JFrame {
    private static final String[] gapList = {"0", "10", "15", "20"};
    private final static int maxGap = 20;
    private JComboBox<String> horGapComboBox;
    private JComboBox<String> verGapComboBox;
    private JButton applyButton = new JButton("Apply gaps");
    private GridLayout experimentLayout = new GridLayout(0,2);

    private GridLayoutDemo(String name) {
        super(name);
        setResizable(false);
    }

    private void initGaps() {
        horGapComboBox = new JComboBox<>(gapList);
        verGapComboBox = new JComboBox<>(gapList);
    }

    private void addComponentsToPane(final Container pane) {
        initGaps();
        final JPanel compsToExperiment = new JPanel();
        compsToExperiment.setLayout(experimentLayout);
        JPanel controls = new JPanel();
        controls.setLayout(new GridLayout(2,3));

        //Set up components preferred size
        JButton b = new JButton("Just fake button");
        Dimension buttonSize = b.getPreferredSize();
        compsToExperiment.setPreferredSize(new Dimension((int)(buttonSize.getWidth() * 2.5)+maxGap,
                (int)(buttonSize.getHeight() * 3.5)+maxGap * 2));

        //Add buttons to experiment with Grid Layout
        compsToExperiment.add(new JButton("Button 1"));
        compsToExperiment.add(new JButton("Button 2"));
        compsToExperiment.add(new JButton("Button 3"));
        compsToExperiment.add(new JButton("Long-Named Button 4"));
        compsToExperiment.add(new JButton("5"));

        //Add controls to set up horizontal and vertical gaps
        controls.add(new Label("Horizontal gap:"));
        controls.add(new Label("Vertical gap:"));
        controls.add(new Label(" "));
        controls.add(horGapComboBox);
        controls.add(verGapComboBox);
        controls.add(applyButton);

        //Process the Apply gaps button press
        applyButton.addActionListener(e -> {
            //Get the horizontal gap value
            String horGap = (String)horGapComboBox.getSelectedItem();
            //Get the vertical gap value
            String verGap = (String)verGapComboBox.getSelectedItem();
            //Set up the horizontal gap value
            assert horGap != null;
            experimentLayout.setHgap(Integer.parseInt(horGap));
            //Set up the vertical gap value
            assert verGap != null;
            experimentLayout.setVgap(Integer.parseInt(verGap));
            //Set up the layout of the buttons
            experimentLayout.layoutContainer(compsToExperiment);
        });
        pane.add(compsToExperiment, BorderLayout.NORTH);
        pane.add(new JSeparator(), BorderLayout.CENTER);
        pane.add(controls, BorderLayout.SOUTH);
    }

    /**
     * Create the GUI and show it.  For thread safety,
     * this method is invoked from the
     * event dispatch thread.
     */
    private static void createAndShowGUI() {
        //Create and set up the window.
        GridLayoutDemo frame = new GridLayoutDemo("GridLayoutDemo");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        //Set up the content pane.
        frame.addComponentsToPane(frame.getContentPane());
        //Display the window.
        frame.pack();
        frame.setVisible(true);
        frame.setLocationRelativeTo(null);
    }

    public static void main(String[] args) {
        /* Use an appropriate Look and Feel */
        try {
            //UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
            UIManager.setLookAndFeel("javax.swing.plaf.metal.MetalLookAndFeel");
        } catch (UnsupportedLookAndFeelException | IllegalAccessException | InstantiationException | ClassNotFoundException ex) {
            ex.printStackTrace();
        }
        /* Turn off metal's use of bold fonts */
        UIManager.put("swing.boldMetal", Boolean.FALSE);

        //Schedule a job for the event dispatch thread:
        //creating and showing this application's GUI.
        javax.swing.SwingUtilities.invokeLater(GridLayoutDemo::createAndShowGUI);
    }
}
